This invention relates to a window or door construction for sealing window or door frames to a wall.
Development of nail-on windows occurred in the 1970""s and originally incorporated aluminum frames and then vinyl frames, which comprise the majority of residential windows.
The window assembly must be water tight within the exterior wall and must be flashed. The flashing seals the window into the exterior wall opening to establish resistance to air and water infiltration. The degree of water resistance should match that of the adjoining wall cladding while the material must breath to allow for outward migration of moisture vapor.
Windows are prefabricated assemblies that are installed into typical frame or other construction walls. The problem of installation of such assemblies is to provide seals for resisting water and moisture penetration at the transition between window frame and the wall structure""s xe2x80x98rough openingxe2x80x99. Windows typically are sealed to the frames with flashing materials in combination with adjoining weather resistive barrier (WRB) materials. Asphalt-based flashings and laminated flashings and building papers do not resist constant exposure to water or continuous cycles of wetting and drying commonly associated with the subject portion of the building envelope.
Window assemblies of recent design have integral nailing flanges which are used to nail the assemblies to the wall frame construction. The altered methods of window installation inherent to these xe2x80x98nail-on windowsxe2x80x99 require an altered method of flashing the window to the exterior wall weatherproofing.
Nailing flanges provide a method of securing the window to the exterior wall framing. They also provide a flat surface onto which a flashing component and sealant can be applied and compressed to create a waterproof seal. Typically, the nailing flange is used as a transition point for the weather resistive barrier installed at adjoining wall areas.
In FIG. 1, a typical nail-on window frame assembly 6 is shown. The assembly 6 includes a glass pane 94 set in a frame 96. Flashing materials 98, 99 and 100 overlap the nailing flanges on the respective head 102, jamb 104 sides of the frame 96 and under the sill flange 106. The flashing materials 98, 99 and 100 are typically of polyethylene material or the like of low permeance, e.g., about 0.30 perms, exhibiting negligible moisture vapor penetration therethrough. The flashing materials 98, 99 and 100 are applied sequentially as separate strips resulting in overlap at regions A, B and so on at each of the corners. The flashing materials are applied with an adhesive to the mating wall construction. Such barriers are available as Moistop E-Z Seal from Fortifiber of Los Angeles, Calif. The material has a vapor permeance of less than about 0.3 perms, as determined following ASTM E96 procedures. This material also is not heat weldable. Other flashing materials may utilize modified bitumen membranes such as Blueskin and Vycor, trademarks for materials used for such membranes as known in this industry.
Due to construction sequencing, the window assembly 6 is typically installed before the flashing materials 98, 99, and 100. In many instances, the flashing materials are improperly lapped onto the nailing flange resulting in leakage. As an improvement, strips of weather resistive barrier or special flashing material (not shown) are installed under the nailing flange on three sides (sill and both jambs) at the time of the window installation. This provides a large area of transition and a material assisting in the formation of a compression seal under the window nailing flange. The seal is, in some applications, augmented by the use of a sealant bead between the underside of the nailing flange and top side of the flashing material. Since the window assemblies 6 are installed during the framing and sheathing process, the flashings are exposed to the weather and can be damaged by weather/exposure.
Once a window assembly with an integral window flange is installed, it is difficult to install a workable flashing without the removal of the window from the opening. The removal can damage the interior window trim and the insulation installed in the framing void between the window profile and the wood framing.
In an effort to design assemblies that can be installed to the outside of a window profile, self-adhering membranes such as the Moistop E-Z Seal noted above have been employed to provide a waterproofing seal. These membranes typically have a very low perm rating trapping moisture vapor at the window perimeter. This can result in deterioration of the wood framing and of the window profile if constructed of wood.
Flashing materials have been developed to wrap the wood framing to the building interior to protect the wood framing from leakage and from the effects of moisture vapor entrapment and condensation accumulation. These materials typically are joined by overlaps, and, in some cases, with a tape to seal the overlaps.
The evolution of both methods of application and materials offered to the market has resulted in the lack of a standardized method of installation and a variety of materials, not all of which are compatible with various weather resistive barriers.
All windows do not provide closed assemblies, and water can leak through the frame that is constructed of individual components mechanically secured at the interior corners. Flashing plays an important role in moisture control of such windows.
Windows are fabricated with mullions, both horizontal and vertical, that are mechanically secured to the window profile and which can leak water. Thus a strong durable seal is needed that can form a full weather tight seal over the entire window opening tying the exterior weather resistive barrier to the interior vapor barrier retarder with an effective flashing seal. While overlaps of prior art strip seals shown in FIG. 1 will shed water, they do not keep water from entering due to pressure differentials. Moreover, joints at the sill create pinholes where the strips intersect at changes of plane. These pinholes are sources of water entry both by gravity flow of water as well as due to pressure differentials. Typically such pinholes may be sealed with dabs of sealant which is not a reliable permanent seal.
Most current flashing assemblies require removal of the window for installation. A flashing material that can be applied to the installed window is a self adhering membrane that is bonded to the outer flange of the window and to the exterior sheathing. That sheathing is usually exterior grade gypsum or engineered wood such as plywood or oriented strand board. Self adhering membranes are usually made of modified bitumen. The combination of the modified bitumen and the adhesive creates a very low perm rating at the seal. This can result in the collection of condensation under the flashing transition and can damage the underlying moisture sensitive components.
Prior to the development of nail-on windows, windows were typically flashed with a metal pan under the window or door. The pan was formed typically of metal or some other rigid material forming a tray. The jamb edges and the back of the sill were turned up to form end dams. The vertical joints were sealed with a sealant or were soldered or welded. The so called tray was especially fabricated to conform to the dimensions of the associated opening. The tray is installed at the ends of the jambs (vertical) or with clips on the rear side. Flashing strips were installed at the jambs running into the tray. Water entering at the head or jambs was directed to the sill tray. The sill tray remained open at the bottom to allow water that enters the assembly to drain out.
Sill trays cannot be used with nail on windows without modification by removing a bottom flange to allow water to exit the assembly. This reduces the strength of the attachment with one plane not attached. Due to potential of compression of wood frame construction, the head of the window is not attached to allow for movement. An alternate method of attachment would be required to modify a nail-on window for use with a sill tray. Sill trays are typically used for flangeless windows that sit in a tray. The nail-on concept is based on sealing the entire window into the opening and creating an air and water barrier on all four sides, yet allowing any water vapor to transfer through the flashing.
There is commercially available a sill tray that is adjustable to fit different size openings.
U.S. Pat. No. 4,555,882 discloses a moisture guard, i.e., a sill tray, for window frames, door jambs and so on. The guard comprises a metallic facing fixed to a rigid plastic molding such as ABS plastic. The sill of a window frame or the sill of a door frame is seated on the metallic facing. The moisture guard has a Z shaped cross section. An integrally formed upstanding rear flange is at the rear edge of the base and an integrally formed depending front flange is at the forward front edge of the base. At an end of the base is formed an end flange with an upstanding vertical wall and with a vertical side wall. The height of the vertical side wall is coextensive with the height of the upstanding end wall and the vertical side wall extends to the depth of the depending front flange. This structure is somewhat as described above in connection with sill trays and has the disadvantages as described therewith. Because the material is of low permeance, it does not allow moisture within the structure to escape. The present inventors recognize that this structure is not as desirable for sealing nail-on window frames and may still be subject to leakage and vapor damage due to interior condensation. It is also not especially adaptable to headers and vertical jambs.
Other flashing and weather stripping arrangements are disclosed in U.S. Pat. Nos. 690,648; 1,411,352; 1,808,336; 2,363,524; 4,126,966; 4,302,262; 4,509,999; 4,700,512; 4,966,819; 5,018,333; 5,086,596 and 5,586,415. None of these are believed to solve the problems discussed herein.
There have been available various methods to form seals and create gaskets at flanges. There has yet to be provided an effective yet flexible system that provides a complete watertight seal out of flexible components that will form to virtually any substrate, eliminate pinholes, provide a durable weatherproofing, easily be sealed to adjoining components, and easily integrated with the wall vapor barrier.
A seal construction according to the present invention is for a nail-on window or door frame, the frame for installation in a window or door opening formed by a horizontal sill, a horizontal head and vertical jambs connecting the sill to the head, the wall at the sill, head and jambs having front and rear faces. The seal construction comprises an integral unitary corner pliable sheet material sealing member that repels liquid water applied to a surface thereof and which permits water vapor to permeate therethrough in response to a pressure differential thereacross to preclude substantial moisture vapor entrapment and condensation collection in the interior of said wall at the window opening while providing a water barrier to liquid water applied thereto. The seal member comprises a first portion for overlying a selected portion of one of the front face at the head and sill, a second portion normal to the first portion and sealingly connected to the first portion for overlying a portion of the jamb at the selected one of the head and sill and a third portion sealingly connected to and normal to the first and second portions for overlying the front face adjacent to the selected one of the head and sill portions and adjacent to the jamb portion.
In one aspect, at least a portion of a first surface of the seal member includes embedded reinforcing fibers for enhancing sealant adherence to the first surface.
In a further aspect, the seal member comprises polyelthylene.
In a further aspect, the first and second portions are each planar connected by a right angle joint therebetween, the third portion comprising an L-shaped member having a first leg depending from the first portion at a right angle thereto and a second leg extending at a right angle to the first leg and extending from the second portion at a right angle thereto.
In a further aspect, a fourth rear portion overlies a portion of the rear face of the selected one of the sill and head, the fourth portion depending from the first portion and juxtaposed with the first leg, and a fifth rear portion extending from the second portion juxtaposed with the second leg for overlying a portion of the rear face of the jamb.
Preferably the first and second portions and a portion of the first and second legs are formed of one piece sheet material, further including a triangular interface section between and bonded to at least a portion of the first and second legs.
In a further aspect, the first and second portions comprise integral one piece sheet material, the first and second portions each having a flange depending therefrom for overlying the rear face and comprising an L-shaped planar sheet member.
In a still further aspect, a method of making a seal construction for a window or door opening in a wall for receiving a nail-on frame for insertion into the opening formed which is formed by a horizontal sill, a horizontal head and vertical jambs connecting the sill to the head, the wall at the sill, head and jambs having front and rear faces. The method comprises forming a flat pliable water impervious first sheet having a permeance sufficient to permit water vaper to permeate therethrough to preclude moisture vapor entrapment and condensation from substantially accumulating on a side thereof at a first edge. A slit is formed in the sheet and has opposing edges. The opposing edges of the slit are spread apart and sealingly attached to a second sheet made of the same material as the first sheet to form a one piece sheet member having a sill or head portion for overlying a sill or head of the opening, a jamb portion for overlying a portion of the jamb normal to the sill or head portion and a front face portion for overlying the front face of the wall at the sill or head and adjacent to the jamb.
The method further comprises forming a rear flange portion extending from a second edge of the sheet material opposite the first edge for overlying a portion of the rear face at the sill or head and jamb.
In a further aspect, the sheet material has a first fold line extending thereacross to opposing second and third edges of the sheet material and a second fold line extending from a fourth edge of the sheet material medially the second and third edges normal to the first fold line and terminating at the first fold line, the slit extending from the junction of the first and second fold lines to the first edge.
In a further aspect, a method of making a seal for a nail-on a window or door opening in a wall, the opening being formed by a horizontal sill, a horizontal head and vertical jambs connecting the sill to the head in the wall, the wall at the sill, head and jambs having front and rear faces, comprises forming a corner seal from a flat sheet of a liquid water repellant pliable material having a permeance sufficient to permit water vapor to pass therethrough in response to a pressure differential across opposing sides of the material to preclude moisture vapor entrapment and condensation on a first side thereof while repelling liquid water incident thereon on a second side, the corner seal comprising a flat first portion for overlying the sill or head and a flat second portion for overlying the jamb, the second portion being integral and one piece with the first portion and forming a flat front face member sealingly attached to the first and second portions for overlying a portion of the front face of the wall at the sill or head and jamb.
In a still further aspect, a method of sealing a window or a door opening in a wall, the opening being formed by a horizontal sill, a horizontal head and vertical jambs connecting the sill and head in the wall, the wall at the sill, head and jambs having front and rear faces, comprises forming a corner seal member of pliable sheet material that repels liquid water applied to a surface thereof and which permits water vapor to permeate therethrough in response to a pressure differential thereacross, the seal member comprising a first portion for overlying a selected portion of one of the sill or head, a second portion normal to the first portion and sealingly connected to the first portion for overlying a portion of the jamb at the selected one of the head and sill and a third front face portion sealingly connected to and normal to the first and second portions for overlying the face of the wall adjacent to the selected one of the head and sill portions and adjacent to the jamb portion. Then attaching the seal member to each of two lower interior corners of the opening at the juncture of the sill and jambs at each end of the sill. Then sill, head and jamb seal members are formed each comprising an elongated L-shape in section member formed of the pliable sheet material and including a first portion for overlying a selected sill, head and jamb and a second portion for overlying the front face; attaching the sill member over the first portions of the corner seal member at each lower corner of the opening and over the sill and over the front face at the sill; and attaching the jamb seal to each vertical jamb over the second jamb portions of each attached corner seal member at the lower corners and over the front face. Then a corner seal member second portion is attached over the jamb seal members at each upper corner of the opening and the first portion over a portion of the head. Finally a head seal member is attached over the first portions of the corner seal members at the head-jamb corners of the frame, and over the head and face.
A retrofit seal construction according to a further aspect of the present invention is for sealing an installed window or door frame in a wall having a front face and a rear face, the frame for enclosing a window or door opening formed by a horizontal sill, a horizontal head and vertical jambs connecting the sill to the head in the wall. The seal construction comprises an integral unitary corner member seal formed of pliable sheet material exhibiting a breathable perm value that repels liquid water applied to a surface thereof and which permits water vapor to permeate therethrough in response to a pressure differential thereacross to preclude substantial condensation collection in the interior of said wall at the opening while providing a water barrier to liquid water applied thereto. The corner member seal comprises an L-shaped planar element of the material with a first leg and a second leg normal to the first leg for overlying the front face adjacent to the sill or head and jamb. A first flange extends outwardly from the first leg for overlying and sealingly attachment to the frame at the sill or head and a second flange extends outwardly from the second leg at a right angle to the first flange for overlying and sealing attachment to the frame at the jamb, the first and second flanges being sealing joined to each other and to the legs at the juncture therebetween and the legs.
A method of sealing a window or door opening in a wall according to a further aspect of the present invention comprises applying pliable sheet material exhibiting a breathable perm value greater than 0.4 that repels liquid water applied to a surface thereof and which permits water vapor to permeate therethrough in response to a pressure differential thereacross to preclude substantial condensation collection in the interior of the wall at the opening while providing a water barrier to liquid water applied thereto to the sill, jambs and head interior surfaces of the window or door opening and to the exterior sheathing at the sill, jambs and head in a bonded plurality of strips of the material.